LIGO Document G1200683-v1:
aLIGO OMC fabrication and testing plan

aLIGO OMC wiki

Facility

• Work
  • Replacing wooden work benches
    • W60" x H28-34" x D30" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60x30-esd-square-edge-power-apron-production-bench-blue
    • W72" x H28-34" x D30" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/72x30-esd-square-edge-power-apron-production-bench-blue
    • Lower shelf W60" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60-w-lower-shelf-bench-15-d-blue 
    • Lower shelf W72" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/72-w-lower-shelf-bench-15-d-blue
  • Replacing a cabinet at the south wall by a lockable cabinet
    • W36" x H72" x D20"
  • Cleaning of the floor
  • Plug a big hole on the wall (Done)
  • Plug slits on the roof of the HEPA booth - "There should be the blanking panels there."
     
  • Install laser Safety curtain (Peter is working on this)
     
  • Place a sticky mat
  • Prepare clean supplies (Shoes/Coverall/Hats/Gloves) => go to VWR stock room
  • Prepare Al foils (All foils inc, should get a certificate everytime to ensure UHV compatibility)
  • Plastic boxes for storage http://www.drillspot.com/products/422140/Rubbermaid_2282-00-CLR_18GAL_Clear_Snap_Case
    (Steve is helping Koji to get them)
     
• Design
  • Optical layout
     
• Test
  • Confirm particle level
     
• Note: Optical Table W96" x D48" x H27"

Mechanics

• Work 
  •  
• Design
  • How do we hold the PDs, QPDs, and black glass - we put 2 PDs and 2 QPDs on the PD mounting blacket.
  •  
•  
• Test
   
• Things to be tested
  • New suspension scheme (cup & cone design)
  • Balancing the plates
  • Dummy metal payload?
• => Suspending test with a suspension cage for a Faraday isolator@CIT
  • Supporting block for the suspension cage (to mimic the OMC suspension)
• Things to be designed
  • Wire end (cone)
  • Diode holding structures
    PD/QPD/PZT holding structure
• PZT alignment
• Prototyping with metal parts?
• UV glue? (heat) / gluing test
• Balance / ballast
   
• Solid works

Optics

• Mirrors to be delivered ~Aug
• Design down select
  • Between "Single output & BS" vs "Two outputs & no BS"
• Mode design
• Finalization of scattering paths / PD angles etc
   
• Things to be decided / confirmed:
  • How to handle optics / assemblies (Talk to the prev people)
  • First contact? (Margot: applicable to a short Rc of ~2.5m)
  • Gluing templates to be designed (how to handle it?)
• Things to be tested:
  • R&T of each mirror
  • Cavity ref/trans/finesse
  • PD QE / incident angle
     
• What PD do we use?
   
• CCD beam analyzer (Zach: It is fixed.)
   
• PD angle measurement
• Obtain EG&G 3mm PDs

Electronics

• Electronics / CDS electronics / software
   
• Things to be tested
  • QPD/PD pre-selections (QE/noise)
  • Functionality test of QPD/PD/PZT

Shipping, storage etc

• Shipping cage drawing
  https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=70209

Jun/July
    - Lab renovtion
    - Mechanics design
    - Glue training
Aug
    - Mirror delivery
    - Basic optics test
Sept
    - Cavity test
    - Suspending test
NOV~DEC
    - Shipping to LLO

Open questions
    Two optical designs
    Procedure
    Modeling
    Clamp design / stencil design
    gluing-installation procedure

EDIT (ZK): All the plots here were generated using my MATLAB cavity modeling tool, ArbCav. The utility description is below. The higher-order mode resonance plots are direct outputs of the function. The overlap plots were made by modifying the function to output a list of all HOM resonant frequencies, and then plotting the closest one as a function of cavity length. This was done for various values of highest mode order to consider, as described in the original entry.

Description:

This function calculates information about an arbitrary optical cavity. It can plot the cavity geometry, calculate the transmission/reflection spectrum, and generate the higher-order mode spectrum for the carrier and up to 2 sets of sidebands.

The code accepts any number of mirrors with any radius of curvature and transmission, and includes any astigmatic effects in its output.

As opposed to the previous version, which converted a limited number of cavity shapes into linear cavities before performing the calculation, this version explicitly propagates the gouy phase of the beam around each leg of the cavity, and is therefore truly able to handle an arbitrary geometry.

----------------Original Post----------------

I expressed concern that arbitrarily choosing some maximum HOM order above which not to consider makes us vulnerable to sitting directly on a slightly-higher-order mode. At first, I figured the best way around this is to apply an appropriate weighting function to the computed HOM frequency spacing. Since this will also have some arbitrariness to it, I have decided to do it in a more straightforward way. Namely, look at the spacing for different values of the maximum mode number, n_max, and then use this extra information to better select the length.

Assumptions:

• The curved mirror RoC is the design value of 2.50±0.025 m
• The ±9 MHz sidebands will have ~1% the power of the other fields at the dark port. Accordingly, as in Sam's note, their calculated spacing is artificially increased by 10 linewidths.
• The opening angle of 4º is FIXED, and the total length is scaled accordingly

Below are the spacing plots for the bowtie (flat-flat-curved-curved) and non-bowtie (flat-curved-flat-curved) configurations. Points on each line should be read out as "there are are no modes of order N or lower within [Y value] linewidths of the carrier TEM₀₀ transmission", where N is the n_max appropriate for that trace. Intuitively, as more orders are included, the maxima go down, because more orders are added to the calculation.

*All calculations are done using my cavity simulation function, ArbCav. The mode spacing is calculated for each particular geometry by explicitly propagating the gouy phase through each leg of the cavity, rather than by finding an equivalent linear cavity*

Since achievable HOM rejection is only one of the criteria that should be used to choose between the two topologies, the idea is to pick one length solution for EACH topology. Basically, one maximum should be chosen for each plot, based on how how high an order we care about.

Bowtie

For the bowtie, the n_max = 20 maximum at L = 1.145 m is attractive, because there are no n < 20 modes within 5 linewidths, and no n < 25 modes within ~4.5 linewidths. However, this means that there are also n < 10 modes within 5 linewidths, while they could be pushed (BLUE line) to ~8.5 linewidths at the expense of proximity to n > 15 modes.

Therefore, it's probably best to pick something between the red and green maxima: 1.145 m < L < 1.152 m.

By manually inspecting the HOM spectrum for n_max = 20, it seems that L = 1.150 m is the best choice. In the HOM zoom plot below and the one to follow, the legend is as follows

• BLUE: Carrier
• GREEN: +9 MHz
• RED: -9 MHz
• CYAN: +45 MHz
• BLACK: -45 MHz

Non-bowtie

Following the same logic as above, the most obvious choice for the non-bowtie is somewhere between the red maximum at 1.241 m and the magenta maximum at 1.248 m. This still allows for reasonable suppression of the n < 10 modes without sacrificing the n < 15 mode suppression completely.

Upon inspection, I suggest L = 1.246 m

I reiterate that these calculations are taking into account modes of up to n ~ 20. If there is a reason we really only care about a lower order than this, then we can do better. Otherwise, this is a nice compromise between full low-order mode isolation and not sitting directly on slightly higher modes.

RoC dependence

One complication that arises is that all of these are highly dependent on the actual RoC of the mirrors. Unfortunately, even the quoted tolerance of ±1% makes a difference. Below is a rendering of the RED traces (n_max = 20) in the first two plots, but for R varying by ±2% (i.e., for R = 2.45 m, 2.50 m, 2.55 m).

The case for the non-bowtie only superficially seems better; the important spacing is the large one between the three highest peaks centered around 1.24 m.

Also unfortunately, this strong dependence is also true for the lowest-order modes. Below is the same two plots, but for the BLUE (n_max = 10) lines in the first plots.

Therefore, it is prudent not to pick a specific length until the precise RoC of the mirrors is measured.

Conclusion

Assuming the validity of looking at modes between 10 < n < 20, and that the curved mirror RoC is the design value of 2.50 m, the recommended lengths for each case are:

• Bowtie: L_RT = 1.150 m
• Non-bowtie: L_RT = 1.246 m

 HOWEVER, variation within the design tolerance of the mirror RoC will change these numbers appreciably, and so the RoC should be measured before a length is firmly chosen.

EDIT 2 (ZK): As with the previous post, all plots and calculations here are done with my MATLAB cavity modeling utility, ArbCav.

EDIT (ZK): Added input q parameters for OMMT 

I found the nice result that the variation in the optimal length vs. variation in the mirror RoC is roughly linear within the ±1% RoC tolerance. So, we can choose two baseline mode definitions (one for each mirror topology) and then adjust as necessary following our RoC measurements.

Bowtie

For R = 2.5 m, the optimal length (see previous post) is L_RT = 1.150 m, and the variation in this is dL_RT/dR ~ +0.44 m/m.

Here is an illustration of the geometry:

The input q parameters, defined at the point over the edge of the OMC slab where the beam first crosses---(40mm, 150mm) on the OptoCad drawing---are, in meters:

• q_ix = - 0.2276 + 0.6955 i
• q_iy = - 0.2276 + 0.6980 i

Non-bowtie

For R = 2.5 m, the optimal length is L_RT = 1.246 m, and the variation in this is also dL_RT/dR ~ +0.44 m/m.

Geometry:

q parameters, defined as above:

• q_ix = - 0.0830 + 0.8245 i
• q_iy = - 0.0830 + 0.8268 i

Here is the proposed RoC measurement setup. Koji tells me that this is referred to as "Anderson's method".

We would like to use a linear cavity to measure the RoC of the curved mirrors independently (before forming the ring cavity), since the degeneracy of HOMs will make the fitting easier.

• An NPRO is PDH locked to a linear cavity formed of a high-quality flat mirror on one end, and the OMC curved optic on the other.
• A second, broadband EOM is placed after the first one, and its frequency is swept with a VCO to generate symmetric sidebands about the carrier
• A TRANS RFPD's signal is demodulated at the secondary EOM frequency, to give a DC signal proportional to HOM transmission
• This HOM scan is fit to a model, with RoC the free parameter. Since there are two sidebands, the HOM spectrum of the model must be folded about the carrier frequency.
• To get a good signal, we should slightly misalign the input beam, allowing for higher overlap with HOMs.

If we decided that the symmetric sidebands are too unwieldy, or that we have issues from sidebands on sidebands, we can accomplish the same style measurement using an AOM-shifted pickoff of the pre-PDH EOM beam. The advantage of the former method is that we don't have to use any polarization tricks.

Facility/Supplies

• Work in progress
  
  • Floor cleaning
  • Plug slits on the roof of the HEPA booth - blanking panels have been ordered (Peter)
  • Install laser safety barrier (Peter is working on this)
  • Place a sticky mat
     
• Work to be done
  • Replacing a file cabinet next to the south wall by a lockable cabinet
  • Replacing a lab desk at the west side of the room. (Vladimir's)
  • Replacing Vladimir's rack with nicer one.
  • Laser sign
  • Safety glass holder
  • Prepare clean supplies (Shoes/Coverall/Hats/Gloves) => go to VWR stock room
    
    • glove 8.5,9,9.5
       
  • Label maker (P-Touch) & Tape
     　
• Design
  • Optical layout - Laser SOP
  • Additional HEPA stage
     
• Test
  • Confirm particle level
     
• Note: Optical Table W96" x D48" x H27"

Beaurocracy

• Laser SOP
• HV use?
• UV?

Mechanics

• Ongoing Work 
  • Cone-shaped wire clamp design (at the OMC end) - Jeff
     
• Design
  • Wire preparation fixture - Jeff
  • How do we hold the PDs, QPDs, and black glass - we put 2 PDs and 2 QPDs on the PD mounting blacket. - Jeff
  • Integrated solidwork model - Sam
    • Q: How the wires are clamped at the top side?
    • Q: How much the length of the wire should be?
    • Q: Locations of the wire mounts on the plate
  • Cabling investigation:
    • Where do the cables from the feed-thrus anchored? - Sam
    • List of the current internal cables and their lengths - Sam
    • List of the required internal cables and their lengths
    • Can we route the intermediate stage of the suspension? Do we need new cables?
  • Dummy intermediate stage structure
     
  • Metal templates
    • First, decide an optical design
    • takes at least a month
       
  • Weights how heavy / how many
     
• Test
  • Cone-shaped wire clamp test - Jeff/Koji 
  • Balancing the plates
    • The Faraday isolator cage isn't clean
  • Dummy metal payload test at the sites???
     
• Procedures to be decided
  • PZT alignment
  • Prototyping with metal parts?
  • UV glue? (heat) / gluing test
  • Balance

Optics

• Ongoing Work 
  
  • Mirrors to be delivered ~Aug
     
  • Design down select - Between "Single output & BS" vs "Two outputs & no BS"
  • Down selecting procedure:
    
    1. Assume ELIGO beam component
    2. Assume amount of 9MHz / 45MHz sidebands at the OMC input
    3. Calculate transmitted power
    4. Require HOM to be smaller than the TEM00 offset 
        
  • UV cured epoxy (Quate obtained)
    
    • Electronic Materials Inc.'s Optocast 3553LV-UTF-HM
      (A Low Viscosity, Ultra Thin Film epoxy with Heat Mechanism. The assembly/cure procedure includes both a UV binding step and a 120 degree cure for 24 hours.)
    • Ref1: Dennis Coyne, LIGO-E960050-v11,
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=3879
    • Ref2: Tobin Fricke, LIGO Document P1000010-v1, Homodyne detection for laser-interferometric gravitational wave detectors
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=8443
    • Ref3: OMC Construction Wiki https://awiki.ligo-wa.caltech.edu/aLIGO/OMC_Construction
    • The glue should be stored at T<0degC ==> Freezer in a lab
       
• Design
  
  • Mode design for HAM6 layout
  • Finalization of scattering paths
     
• Tests
  • Measurement of PD angles
  • R&T of each mirror
  • Curvature of the curved mirrors
  • Cavity ref/trans/finesse
  • PD Q.E. & Reflectivity measurement vs incident angle
     
• Things to be decided / confirmed
  • How to handle optics / assemblies (Talk to the prev people)
  • First contact? (Margot: applicable to a short Rc of ~2.5m)
  • Gluing templates to be designed (how to handle it?)
     
• PDs
  • Primary choice for DC PD: Exelitas C30665GH 3mm
    0.76A/W => Q.E. 0.88
    http://www.excelitas.com/downloads/dts_pe_pd_14_ingaasandsipindiodes.pdf
     
  • Primary choice for DC QPD: OSI FCI-InGaAs-Q3000
     
• Misc
  • CCD beam analyzer (Zach: It is fixed.)
  • Are two PZTs used?
    • YES, for redundancy, range, upconversion tests.
       
• Things to buy
  • Obtain EG&G 3mm PDs
  • Black Glass / Black Glass holder
  • Acetone.
  • N2 cylinder: 4N - UHP or 5N - Research Grade.
  • Paper lens tissue
  • Lint free cloth
  • The ionized gun used in the clean room at Downs: made by Terra Universal.com
    http://www.terrauniversal.com/static-control/ionizing-blow-off-guns.php
  • Flow path: N2 cylinder - Filter - Gun
  • Freezer

• Need to buy a fiber for mode cleaning?
  
• Mode content of the ELIGO dark beam?
• Jitter noise?
• How to determine the design?
• Why Fused Silica? (How much is the temp fluctuation in the chamber?)
• How to align the cavity mirrors, input mirrors, QPDs, PDs, beam dumps.
   

Electronics

• Thorough scrutinization of cabling / wiring / electronics
• Electronics / CDS electronics / software
• Things to be tested
  • QPD/PD pre-selections (QE/noise)
  • Functionality test of QPD/PD/PZT

Shipping, storage etc

• Shipping cage drawing
  https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=70209

Jun/July
    - Lab renovtion
    - Mechanics design
    - Glue training
Aug
    - Mirror delivery
    - Basic optics test
Sept
    - Cavity test
    - Suspending test
NOV~DEC
    - Shipping to LLO

Open questions
    Two optical designs
    Procedure
    Modeling
    Clamp design / stencil design
    gluing-installation procedure

July:Facility/Supplies

• Completed Work: Facility/Supplies
  • Plug a big hole on the wall
  • Purchasing work benches
    
    • W60" x H28-34" x D30" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60x30-esd-square-edge-power-apron-production-bench-blue
    • Lower shelf W60" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60-w-lower-shelf-bench-15-d-blue
  • Wooden work benches removed(arranging the work with Louisa)
     
  • Al foils (All foils inc, should get a certificate everytime to ensure UHV compatibility)
  • Laser / UV safety glass/face mask (Ordered with Gina, UV face shield ordered through Techmart)
    • 35-200 Laser Glasses (PN 100-35-200) Qty.2 Price 189.00 ea
      http://www.lasersafetyindustries.com/35_200_Laser_Safety_Glasses_p/35-200.htm
    • Black Sport-wrap Laser Glasses 950-3600 nm (PN 100-38-200) Qty.1 Price 169.00 ea
      http://www.lasersafetyindustries.com/Black_Sport_wrap_Glasses_Diode_Nd_YAG_Er_YAG_p/100-38-200.htm
    • VWR has FACE SHIELD UVC-803 and this is ANSI-Z87.1 1986 compliant and the O.D. is more than 5.
      https://us.vwr.com/store/catalog/product.jsp?catalog_number=33007-151
  • Sticky mat
    
    • VWR MAT ADHESIVE 30L 18X36 BLU, 21924-110
  • Shoe cover
    • VWR SHOECVR NSKID AP XL 150PR, 414004-650
    • VWR SHOECVR NSKID AP 2XL 150PR, 414004-651
  • Lab coat
    
    • VWR Lab coat L 82007-618 / XL 82007-620
  • Hat
    
    • VWR Hat 10843-053
  • Mask
    
    • VWR Face Masks 10869-020
  • Gloves
    
    • VWR GLOVE ACCTCH NR-LTX SZ7.5 PK25 79999-306 x4
    • VWR GLOVE ACCTCH NR-LTX SZ8 PK25 79999-308 x4
  • Plastic boxes for storage
    http://www.drillspot.com/products/422140/Rubbermaid_2282-00-CLR_18GAL_Clear_Snap_Case
    (We have 12 for now. More stored at the 40m)
     
• Completed Work: Optics
  • UV Lamp arrived (shipped from LLO)
    
  • Fiber light guide for UV lamp (Quote obtained / Ordered via techmart) 

Nic Smith sent me a bunch of elog lists where the results of the mode scan can be found.

From Nic:

There have been many mode scan analyses done at LLO:
http://ilog.ligo-la.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=06/07/2008&anchor_to_scroll_to=2008:06:07:20:55:41-jrsmith
http://ilog.ligo-la.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=06/16/2008&anchor_to_scroll_to=2008:06:16:17:47:11-waldman
http://ilog.ligo-la.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=08/06/2009&anchor_to_scroll_to=2009:08:06:12:23:16-kissel
http://ilog.ligo-la.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=09/25/2009&anchor_to_scroll_to=2009:09:25:20:57:47-kate

We didn't do as much of this at LHO. At some point we were trying to figure out how the arm cavity mode was different from the carrier mode:
http://ilog.ligo-wa.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=04/17/2009&anchor_to_scroll_to=2009:04:17:23:15:05-kawabe
http://ilog.ligo-wa.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=03/27/2009&anchor_to_scroll_to=2009:03:27:21:38:14-kawabe
http://ilog.ligo-wa.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=02/18/2009&anchor_to_scroll_to=2009:02:18:20:15:00-kawabe

Here's a long mode scan that was done, and the data is attached to the elog, but none of the amplitudes are analyzed.
http://ilog.ligo-wa.caltech.edu/ilog/pub/ilog.cgi?group=detector&date_to_view=07/08/2009&anchor_to_scroll_to=2009:07:08:17:02:19-nicolas

Here is a more detailed version of the setup, so that we can gather the parts we will need.

Parts list:

• Optics, etc.:
  • 1 NPRO
  • 2 QWP
  • 3 HWP
  • 2 PBS
  • 2 EOM (at least one broadband)
  • 2 RFPD (at least one very-high-bandwidth for TRANS, e.g., 1611)
  • 1 CCD camera
  • OMC curved mirrors to be tested
  • 1 low-loss flat reference mirror with appropriate transmission (e.g., G&H, ATF, etc.)
  • ~3 long-ish lenses for MMT, EOM focusing
  • ~2 short lenses for PD focusing
  • 1 R ~ 80% power splitter for TRANS (can be more or less)
  • ~7 steering mirrors
  • ~3 beam dumps
  • Mounts, bases, clamps, hardware
• Electronics:
  • 1 fixed RF oscillator (e.g., DS345, etc.)
  • 1 VCO (e.g., Marconi, Tektronix, etc.)
  • 2 Minicircuits RF mixers
  • 2 Minicircuits RF splitters
  • 2 SMA inline LPFs
  • Locking servo (SR560? uPDH? PDH2?)
  • Some digital acquisition/FG system
  • Power supplies, wiring and cabling.

I consulted with Margot about the cleaning of the optics

• Optics are considered as a clean object. Large dusts can be removed by ionized N2 flow etc.
• Barrel of optics can be wiped with Acetone.
• Optical surfaces are best to be cleaned by First Contact.
• A peek mesh should be embedded in the first contact so that the First Contact sheet can be easily removed.
• When peeling a F.C. sheet from a mirror surface, ionized N2 should be brown for discharging.
• If there are residuals visible on the mirror surface, it should be removed by Acetone. Don't use alchols.
• Use paper lens tissue for wiping as the lint free wipe can be eaten by Acetone.
• In fact, All of the procedure is described in a certain document.
• For a small amount, Margot can provide us a bottle of F.C. and some PEEK meshes.

Details of the Ionized N2 system

• This N2 should have higher purity than 4N (UHP - Ultra High Purity). This means we should use 4N - UHP or 5N - Research Grade.
• The ionized gun used in the clean room at Downs: made by Terra Universal.com
• Flow path: N2 cylinder - Filter - Gun

Nicolas Smith,
LIGO Document T0900383-v1
3mm Photodiode Characterization for Enhanced LIGO
https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=4498

Tobin Fricke,
LIGO Document P1000010-v1
Homodyne detection for laser-interferometric gravitational wave detectors
https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=8443

Nicolas Smith,
LIGO Document P1200052-v1
Techniques for Improving the Readout Sensitivity of Gravitational Wave Antennae
https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=90498

• Completed Work: Facility/Supplies
  • Plug a big hole on the wall [ELOG]
  • Purchasing work benches
    
    • W60" x H28-34" x D30" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60x30-esd-square-edge-power-apron-production-bench-blue
    • Lower shelf W60" http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/60-w-lower-shelf-bench-15-d-blue
  • Wooden work benches removed(arranging the work with Louisa)
     
  • Al foils (All foils inc, should get a certificate everytime to ensure UHV compatibility)
  • Laser / UV safety glass/face mask (Ordered with Gina, UV face shield ordered through Techmart)
    • 35-200 Laser Glasses (PN 100-35-200) Qty.2 Price 189.00 ea
      http://www.lasersafetyindustries.com/35_200_Laser_Safety_Glasses_p/35-200.htm
    • Black Sport-wrap Laser Glasses 950-3600 nm (PN 100-38-200) Qty.1 Price 169.00 ea
      http://www.lasersafetyindustries.com/Black_Sport_wrap_Glasses_Diode_Nd_YAG_Er_YAG_p/100-38-200.htm
    • VWR has FACE SHIELD UVC-803 and this is ANSI-Z87.1 1986 compliant and the O.D. is more than 5.
      https://us.vwr.com/store/catalog/product.jsp?catalog_number=33007-151
  • Sticky mat
    
    • VWR MAT ADHESIVE 30L 18X36 BLU, 21924-110
  • Shoe cover
    • VWR SHOECVR NSKID AP XL 150PR, 414004-650
    • VWR SHOECVR NSKID AP 2XL 150PR, 414004-651
  • Lab coat
    
    • VWR Lab coat L 82007-618 / XL 82007-620
  • Hat
    
    • VWR Hat 10843-053
  • Mask
    
    • VWR Face Masks 10869-020
  • Gloves
    
    • VWR GLOVE ACCTCH NR-LTX SZ7.5 PK25 79999-306 x4
    • VWR GLOVE ACCTCH NR-LTX SZ8 PK25 79999-308 x4
  • Plastic boxes for storage
    http://www.drillspot.com/products/422140/Rubbermaid_2282-00-CLR_18GAL_Clear_Snap_Case
    (We have 12 for now. More stored at the 40m)
     
• Completed Work: Optics
  • UV Lamp arrived (shipped from LLO)
    
  • Fiber light guide for UV lamp (Quote obtained / Ordered via techmart)
  • Optical test planning by Zach [ELOG]
  • How to handle First Contact by Margot [ELOG]
  • Useful links / OMC scanning [ELOG]

Completed work of the previous months: [Jul] [Aug] [Sep] [Oct] [Nov] [Dec]

Facility/Supplies

• Work done
  • Floor cleaning [ELOG]
  • Placing sticky mats [ELOG]
  • Label Maker purchased
  • Ordered a lab desk at the west side of the room
    http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/72-l-x-36-w-production-bench-esd-square-edge-blue-2
  • Ordered clean / ESD  stools (~25" height)
    http://www.globalindustrial.com/p/office/stools/vinyl/esd-safe-vinyl-clean-room-stool-with-nylon-base-with-drag-chain-blue
  • Asked Gina for the electronics rack
    www.racksolutions.com/server-racks-cabinets-enclosures.html
    36U Height / 20" depth + Caster kit
  • 5 shelves ordered from AlliedElectronics (Quest technology ES0319-0115, 19"x15" non-vented shelf)
    http://www.racksolutions.com/rack-shelves
  • Plug slits on the roof of the HEPA booth (Peter)
  • Laser safety barrier (Peter) [ELOG]
  • Workbenches and clean room stools [ELOG]
     
• Things ordered
  
  • Office Depot
    • [delivered] Office Depot(R) Brand Stretch Wrap Film, 20 x 1000 Roll, Clear / 445013
    • [delivered] Eveready(R) Gold AA Alkaline Batteries, Pack Of 24 / 158448
    • [delivered] Rubbermaid(R) Roller Sponge Mop / 921841
    • [delivered] Rubbermaid(R) Roller Sponge Mop Replacement / 921858
    • [delivered] Rubbermaid(R) Sanitizing Caddy, 10 Quarts, Yellow / 674125
    • [delivered] Glad(R) Tall Kitchen Trash Bags, 13 Gallon, White, Box Of 28 / 269268
  • Global Industrial Equipment
    
    • [delivered] Extended Surface Pleated Cartridge Filter Serva-Cell Mp4 Slmp295 12X24X2 Gl    WBB431699
  • Global Industrial Equipment
    
    • [delivered] Nexel Poly-Z-Brite Wire Shelving 30"W x 21"D x 63"H Nexel Poly-Z-Brite™ Wire Shelving Starter Unit WB189209
    • [delivered] Stem Casters Set of (4) 5" Polyurethane Wheel, 2 With Brakes 1200 lb. Capacity WB500592    
  • Rack Solutions
    • [delivered] Open Frame Server Racks
      1 x 20" Depth Kit (Ideal for Audio/Video or Networking Racks) P/N: 111-1779
      1 x 36U, Rack-111 Post Kit P/N: 111-1728
      1 x Caster Kit for Open Frame RACK-111 P/N: 111-1731
    • [delivered] 36U Side Panel Kit $199.99 P/N: 102-1775
  • Rack shelf
    • [delivered] 1 RMS 19 X 15 SINGLE SIDED NON-VENTED SHELF 70121637
  • Work bench, Stools
    • [not yet] 72"L X 30"W Production Bench - Phenolic Resin Square Edge-Blue Form attached WB237381LBL    
    • [not yet] 72"W Lower Shelf For Bench - 15"D- Blue Form attached WB606951    
    • [not yet] ESD-Safe Vinyl Clean Room Stool with Nylon Base with Drag Chain Blue Form attached WBB560852    
  • P Touch
    • [delivered] Brother PT-2030 Desktop Office Labeler Punch-out product 672828    
    • [delivered] Brother(R) TZe-241 Black-On-White Tape, 0.75 x 26.2 Punch-out product 239384    
    • [delivered] Brother(R) TZe-231 Black-On-White Tape, 0.5 x 26.2 Punch-out product 239400    
      
  • UV light guide
    • [delivered] Fiber Optic Single Light Guide 5mm OD X 3mm ID X 1M L Note: This light guide can be used with MKIII UV Cure unit. OLB1081
  • Gloves (7.5, 8.0)
    • [delivered] GLOVE ACCTCH NR-LTX SZ7.5 PK25 Punch-out product 79999-306
    • [delivered] GLOVE ACCTCH NR-LTX SZ8 PK25 Punch-out product 79999-308
  • Lab coat (L,XL), Sticky Mat, Shoe Covers (L, XL), Cap, Mask
    • [delivered] LAB XP WH EL WR.COLL. NP L30EA Punch-out product 82007-618
    • [delivered] LAB XPWH EL WR.COLL. NP XL30EA Punch-out product 82007-620    
    • [delivered] VWR MAT ADHESIVE 30L 18X36 BLU Punch-out product 21924-110 (This was too small)
    • [delivered] VWR SHOECVR NSKID AP 2XL 150PR Punch-out product 414004-651    
    • [delivered] VWR SHOECVR NSKID AP XL 150PR Punch-out product 414004-650    
    • [delivered] CAP BOUFFANT 24IN RAYON CS500 Punch-out product 10843-053    
    • [delivered] MASK VLTC TIES N/STRL PK50 Punch-out product 10869-020
      
  • VWR
    • [delivered] FACE SHIELD UVC-803 Supplier: UVP 33007-151
       
  • [Delivered] Laser safety glasses
    
    • 35-200 Laser Glasses (PN 100-35-200) Qty.2 Price 189.00 ea
      http://www.lasersafetyindustries.com/35_200_Laser_Safety_Glasses_p/35-200.htm
    • Black Sport-wrap Laser Glasses 950-3600 nm (PN 100-38-200) Qty.1 Price 169.00 ea
      http://www.lasersafetyindustries.com/Black_Sport_wrap_Glasses_Diode_Nd_YAG_Er_YAG_p/100-38-200.htm

• Work in progress
  
  • 
     
• Work to be done
  • Replacing a file cabinet next to the south wall by a lockable cabinet
  • Laser sign
  • Safety glass holder/rack/shelf
  • Prepare clean supplies ~ glove 8.5,9,9.5
  • Ion gun safety issues: https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=88631
     　
• Design
  • Optical layout - Laser SOP
  • Additional HEPA stage
     
• Test
  • Confirm particle level
     
• Note: Optical Table W96" x D48" x H27"

Beaurocracy

• Laser SOP
• HV use?
• UV?

Mechanics

• Ongoing Work 
  • Cone-shaped wire clamp design (at the OMC end) - Jeff
     
• Design
  • Wire preparation fixture - Jeff
  • How do we hold the PDs, QPDs, and black glass - we put 2 PDs and 2 QPDs on the PD mounting blacket. - Jeff
  • Integrated solidwork model - Derek
    • Q: How the wires are clamped at the top side?
    • Q: How much the length of the wire should be?
    • Q: Locations of the wire mounts on the plate
  • Cabling investigation:
    • Where do the cables from the feed-thrus anchored?
    • List of the current internal cables and their lengths
    • List of the required internal cables and their lengths
    • Can we route the intermediate stage of the suspension? Do we need new cables?
  • Dummy intermediate stage structure
     
  • Metal templates
    • First, decide an optical design
    • takes at least a month
       
  • Weights how heavy / how many
     
  • Earthquake stop design (Sam B)
     
• Test
  • Cone-shaped wire clamp test - Jeff/Koji 
  • Balancing the plates
    • The Faraday isolator cage isn't clean
  • Dummy metal payload test at the sites???
     
• Procedures to be decided
  • PZT alignment
  • Prototyping with metal parts?
  • UV glue? (heat) / gluing test
  • Balance

Optics

• Things ordered
  
  • Newport LB servo
  • Halogen Lamp
  • N2 cylinder/lines/filter
• Ongoing Work 
  
  • Mirrors to be delivered ~Aug
     
  • Design down select - Between "Single output & BS" vs "Two outputs & no BS"
  • Down selecting procedure:
    
    1. Assume ELIGO beam component
    2. Assume amount of 9MHz / 45MHz sidebands at the OMC input
    3. Calculate transmitted power
    4. Require HOM to be smaller than the TEM00 offset 
        
  • UV cured epoxy (Quate obtained)
    
    • Electronic Materials Inc.'s Optocast 3553LV-UTF-HM
      (A Low Viscosity, Ultra Thin Film epoxy with Heat Mechanism. The assembly/cure procedure includes both a UV binding step and a 120 degree cure for 24 hours.)
    • Ref1: Dennis Coyne, LIGO-E960050-v11,
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=3879
    • Ref2: Tobin Fricke, LIGO Document P1000010-v1, Homodyne detection for laser-interferometric gravitational wave detectors
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=8443
    • Ref3: OMC Construction Wiki https://awiki.ligo-wa.caltech.edu/aLIGO/OMC_Construction
    • The glue should be stored at T<0degC ==> Freezer in a lab
       
• Design
  
  • Mode design for HAM6 layout
  • Finalization of scattering paths
     
• Tests
  • Measurement of PD angles
  • R&T of each mirror
  • Curvature of the curved mirrors
  • Cavity ref/trans/finesse
  • PD Q.E. & Reflectivity measurement vs incident angle
     
• Things to be decided / confirmed
  • How to handle optics / assemblies (Talk to the prev people)
  • First contact? (Margot: applicable to a short Rc of ~2.5m)
  • Gluing templates to be designed (how to handle it?)
     
• PDs
  • Primary choice for DC PD: Exelitas C30665GH 3mm
    Peter has plenty of them
    0.76A/W => Q.E. 0.88
    http://www.excelitas.com/downloads/dts_pe_pd_14_ingaasandsipindiodes.pdf
     
  • Primary choice for DC QPD: OSI FCI-InGaAs-Q3000
     
• Misc
  • CCD beam analyzer (Zach: It is fixed.)
  • Are two PZTs used?
    • YES, for redundancy, range, upconversion tests.
       
• Things to buy
  
  • Black Glass / Black Glass holder
  • Acetone.
  • N2 cylinder: 4N - UHP or 5N - Research Grade.
  • Paper lens tissue
  • Lint free cloth
  • The ionized gun used in the clean room at Downs: made by Terra Universal.com
    http://www.terrauniversal.com/static-control/ionizing-blow-off-guns.php
  • Flow path: N2 cylinder - Filter - Gun
  • Freezer
  • Clean tools, tray, storage

• Need to buy a fiber for mode cleaning?
  
• Mode content of the ELIGO dark beam?
• Jitter noise?
• How to determine the design?
• Why Fused Silica? (How much is the temp fluctuation in the chamber?)
• How to align the cavity mirrors, input mirrors, QPDs, PDs, beam dumps.
• PZTs @LLO
   

Electronics

• Thorough scrutinization of cabling / wiring / electronics
  • ELIGO OMC Wiring diagram D070536-A2
    • Occupies 2 DB25s -> They were anchored on the sus cage
    • Preamps for DCPDs will be fixed on the ISI table
      -> DB25 for the DCPDs will be anchored on the table
    • Use longer thin cables for the DCPDs in order to route them through the suspension stages
    • Turn the heater cable to the one for the other PZT
• Electronics / CDS electronics / software
• Things to be tested
  • QPD/PD pre-selections (QE/noise)
  • PD preamp design (Rich)
  • Functionality test of QPD/PD/PZT

Shipping, storage etc

• Shipping cage drawing
  https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=70209

Jun/July
    - Lab renovation
Aug
    - Mechanics design
    - Mirror delivery
Sept
    - Basic optics test
    - Glue training
Oct
    - Cavity test
Nov
    - Suspending test
Dec
    - Shipping to LLO

Open questions
    Two optical designs
    Procedure
    Modeling
    Clamp design / stencil design
    gluing-installation procedure

- The floor of the room was cleaned and waxed!

- Sticky mats are placed! Now we require shoe covers!

- Work benches are being built. One unit is done.

- The other is half done because the table top has chippings.

It seemed that a laser safety barrier was installed today!?

Floor wiped with a wet wiper (Aug 13, 2012)
Floor wiped with a wet wiper (Aug 15, 2012)
Floor wiped with a wet wiper (Sep 25, 2012)
Air conditioning prefilter replaced (Sep 25, 2012)
Floor wiped with a wet wiper (Oct 01, 2012)
Floor wiped with a wet wiper (Nov 06, 2012) / ATF too
Floor wiped with a wet wiper (Jan 04, 2013)
Floor wiped with a wet wiper (Mar 23, 2013)
Floor wiped with a wet wiper (Apr 17, 2013)
Air conditioning prefilter replaced (Apr 17, 2013)
Floor wiped with a wet wiper (Jun 24, 2013)
Removing Vladimir's mess. Floor swept with a broom (Jun 26, 2013)
Completed removing Vladimir's mess. Floor swept with a wet wiper (Jun 27, 2013)
Air conditioning prefilter replaced (Sep 12, 2013)
Floor wiper head replaced. (Dec 10, 2013)
Floor wiped with a wet wiper (Dec 10, 2013)
Floor wiped with a wet wiper (Apr 1, 2014)

Air conditioning prefilter replaced (Dec 30, 2014)
Air conditioning prefilter replaced (some time in 2015...)

Floor wiped with a wet wiper (Dec 1, 2015)
Floor wiped with a wet wiper (Aug 23, 2016)
Air conditioning prefilter replaced (Aug 8, 2017) = 1 stock remains
Air conditioning prefilter replaced (Unkniwn) = no stock remains
Air conditioning prefilter replaced (Jul 25, 2022) = 5 stock remains
Floor wiped with a wet wiper (Mar 7, 2023)

Aug 13, 2012 / 0.5um 1000~2000/(0.1 cu ft) / 0.7um   400-600/(0.1 cu ft) by ATF particle counter (MET ONE 227A)

They are counts/(0.1 ft^3)! These numbers should be multiplied by 10 to know the particle "CLASS".

Clean supplies & some cleaning tools are located at the right side of the entrance.
The file cabinet there was moved to the left side of the door, but will be removed eventually.

Last Friday, new workbenches were installed. Vladimir got a new table and a cleanroom stool.

The other two workbenches were also nicely set.

Particle counts

Before the prefilter is installed: 0.5um 1191cnts, 0.7um 346cnts

2:20 prefilter installed
2:25 0.5um 650 / 0.7um 255
3:00 0.5um 578 / 0.7um 99
4:00 0.5um 480 / 0.7um 102
5:00 0.5um 426 / 0.7um 76

They are counts/(0.1 ft^3)! These numbers should be multiplied by 10 to know the particle "CLASS".

1. It turned out that the particle counter MET ONE 227A at ATF shows
(particle count)/(0.1 ft^3)

This means that the numbers I saw previously should be multiplied by 10.
So the nominal class of the room was 5000.

2. As our GT-321s have no diffuser, I borrowed a diffuser from 227A.
The diffuser actually increases the count. We need to buy them.
All the measurments below are performed with the diffuser and calibrated in Count/ft^3.

3. Measured the particle level without the HEPA running.

With diffuser: [cnt/ft^3]

Over Class 10000

4. The two HEPA fans are turned on at the speed "MED".

Basically no particles are detected in the HEPA booth.

With diffuser, inside of the HEPA booth:

The particle level in the room (outside of the HEPA booth) is also improved

With diffuser, outside of the HEPA booth GT-321 #1:
0.3 um 18612
0.5 um   1728

5. The two HEPA fans are turned on at the speed "LOW".

Particle levels are still zero inside.

With diffuser, inside of the HEPA booth, GT-321 #1:
0.3 um 0
0.5 um 0

The particle level in the room (outside of the HEPA booth) is also improved
but the cleaning power for 0.3um seems degraded.

With diffuser, outside of the HEPA booth, GT-321 #1:
0.3 um 34488
0.5 um   1386

Based on Zach's experiment design, I wrote up a bit more detailed optical layout for the mirror test.

Item: Newfocus Fast PD
Qty.: 1
Mirror: Newfocus Fast PD
Mount: Post
Post: Post Holder (Newfocus)
Fork: Short Fork

Item: Thorlabs RF PD
Qty.: 1
Mirror: Thorlabs RF PD
Mount: Post
Post: Post Holder (Newfocus)
Fork: Short Fork

Item: Newfocus Broadband
Qty.: 1
Mirror: Newfocus EOM
Mount: Newfocus
Post: Custom Mount? or Pedestal X"?
Fork: Short Fork

Item: Newfocus Resonant
Qty.: 1
Mirror: Newfocus EOM
Mount: Newfocus
Post: Custom Mount? or Pedestal X"?
Fork: Short Fork

Item: ND Filter
Qty.: 2
Mirror: -
Mount: Thorlabs FIlter Holder
Post: Pedestal X"
Fork: Short Fork

Item: New Port Lens Kit 1"
Qty.: 1

Item: Thorlabs ND Kit
Qty.: 1

Item: Plano Convex Lens
Qty.: f=100, 100, 150, 200
Mirror: New Port (AR)
Mount: Thorlabs
Post: Post Holder (Newfocus)
Fork: Short Fork

Item: Bi-Convex Lens
Qty.: 75
Mirror: New Port (AR)
Mount: Post
Post: Post Holder (Newfocus)
Fork: Short Fork

Item: Flipper Mirror
Qty.: 1
Mirror: CVI Y1-10XX-45P
Mount: New Focus Flipper
Post: Pedestal X"
Fork: Short Fork

Item: Steering Mirror
Qty.: 8
Mirror: CVI Y1-10XX-45P
Mount: Suprema 1inch
Post: Pedestal X"
Fork: Short Fork

Item: PBS
Qty.: 3
Mirror: PBS 1inch BK7
Mount: Newport BS Mount
Post: Pedestal X"
Fork: Short Fork

Item: Knife Edge Beam Dump
Qty.: 4
Mirror: Thorlabs Knife Edge
Mount: Post
Post: Post Holder (Newfocus)
Fork: Short Fork

Item: Half Wave Plate
Qty.: 4
Mirror: CVI QWPO-
Mount: CVI
Post: Pedestal X"
Fork: Short Fork

Item: Quater Wave Plate
Qty.: 3
Mirror: CVI QWPO-
Mount: CVI
Post: Pedestal X"
Fork: Short Fork

Item: OMC Curved Mirror
Qty.: 2
Mirror: -
Mount: Suprema 0.5inch + Adapter
Post: Pedestal X"
Fork: Short Fork

Item: Prism Holder
Qty.: 1
Mirror: OMC Prism
Mount: Newport Prism Mount
Post: Pedestal X"
Fork: Short Fork

Item: CCD
Qty.: 1
Mirror: Thorlabs?
Mount: Thorlabs?
Post: Post Holder (Newfocus)
Fork: Short Fork

EGE&G 2mm photodiode angle response measured by Sam T1100564-v1

• HWP set
  
  • Optics: CVI QWPO-1064-08-2-R10
  • Mount: New Focus #9401
  • Post: Pedestal 2.5inch
  • Returned: Oct 19, 2012 by KA
• QWP set
  
  • Optics: CVI QWPO-1064-05-4-R10
  • Mount: New Focus #9401
  • Post: Pedestal 2.5inch
  • Returned: Jan 17, 2013 by KA
• Faraday set
  
  • Optics: OFR IO-2-YAG-HP Returned: Mar 21, 2013 by KA
  • Mount: New Focus #9701 Returned: Apr 17, 2013 by KA
  • Post: Pedestal (1.5+0.25inch)x2
• Steering Mirror 1
  
  • Optics: CVI Y1-1037-45S
  • Mount: Newport Ultima U100-AC
  • Post: Pedestal 3inch
  • Returned: Jan 17, 2013 by KA
• Steering Mirror 2
  
  • Optics: CVI Y1-1037-45P
  • Mount: Newport Ultima U100-AC
  • Post: Pedestal 3inch
  • Returned: Jan 17, 2013 by KA
• Steering Mirror 3
  • Optics: New Focus 5104
  • Mount: Newport Ultima U100-AC
  • Post: Pedestal 3inch
  • Returned: Jan 17, 2013 by KA
• Prism Mount
  
  • Mount: Thorlabs KM100P+PM1 2014/7/17
  • Post: Pedestal 1.5+1+1/8inch
• 0.5" Mirror Mount
  
  • Mount: Newport U50-AReturned: Apr 17, 2013 by KA
  • Mount: Newport U50-A 2014/7/17
  • Post: Pedestal 1.5+2inch
• Black Glass Beam Dump
  • Optics: 1" sq. schott glass x3
  • Mount: Custom Hexagonal 1"
  • Post: Pedestal 3inch
• PBS Set
  
  • 05BC16PC.9 (PBS 1064 1000:1)
    
  • Mount: Custom Aluminum
  • Returned: Jan 17, 2013 by KA
• Lenses
  
  • KBX067.AR33 f=125mm
  • KPX106 f=200mm, KPX109 f=250mm unknown-coat
  • KPX088.AR33 f=75mm
  • KPX094.AR33 f=100mm
  • PLCX-C (BK7) 3863 (f=7.5m), 2060 (f=4.0m), 1545 (f=3.0m), 1030 (f=2.0m) non-coat
  • PLCX-UV (FS) 30.9 non-coat(!) f=60mm
  • Returned: Jan 17, 2013 by KA
• Pedestals
  
  • 1/4" x5, 1/8" x3, Returned: Jan 17, 2013 by KA
  • 0.5" x1, 1.5" x1

Another loan from the 40m on Oct 17th, 2012

• Minicircuits
  
  • Splitter ZFSC-2-5 x2
  • Filter SLP-1.9 x2 / BLP-1.9 x1/2 / SLP-5 x1
  • Returned: Jan 17, 2013 by KA
• Connectors / Adaptors
  
  • SMA TEE x1 / SMA 50Ohm x 1 / BNC T x 10, Returned: Jan 17, 2013 by KA
  • SMA TEE x1 / SMA 50Ohm x 1Returned: May 20, 2013 by KA
• Pomona Box x1, Returned: Jan 17, 2013 by KA
• Pomona Box x1
• Power supply for New Focus Fast PD made by Jamie R Returned: Apr 17, 2013 by KA
• BS-1064-50-1037-45S / Newport U100-A mount / 1"+2" Pedestal, Returned: Jan 17, 2013 by KA
• BS-1064-50-1025-45P / Newport U100-A mount / 3/4" post + Base, Returned: Jan 17, 2013 by KA
• BNC cable 21ft x2, Returned: Jan 17, 2013 by KA
• SMA Cable 6ft

Another loan from the 40m on Nov 21th, 2012

• Mounting Base Thorlabs BA-2 x 17
• Mounting Posts (phi=3/4", L=2.65", normal x15, and 1/4"-20 variant x2)

Yet another loan from the 40m on Jan 16th, 2013

• V-groove Mounting Bases Custom. Qty.2Returned: Feb 25, 2013 by KA

Loan from ATF

32.7MHz EOM+Tilt aligner
Thorlabs Broadband EOM+Tilt aligner
Forks x 5Returned: Feb 25, 2013 by KA
JWIN Camera x 2

We have measured the dimensions and mass of the OMC glass plates/breadboards:

• ^* orientation is relative to "front" face, i.e. long-short face with S/N on it, with S/N upright.
• Height measurements were made twice, once at each end.
• TMeasurements of 03, 05, 02, and 06 were done in the open in the OMC lab.  This was not thought to be too much of an issue since the plates
  are already covered with particulate matter from the tissue paper that they were wrapped in. 
  Measurements of 04 and 01 were done on the optics table, under the clean room enclosure.

Note by Koji:

• The scale of the bake lab was used. (Max 60kg, Min resolution of 1g)
• The dimensions were measured by a huge caliper which Jeff brought from Downs.
• S/N 01, 03, 04 look pretty similar. They should be the primary candidates.

• Work done
  • Floor cleaning [ELOG]
  • Placing sticky mats [ELOG]
  • Label Maker purchased
  • Ordered a lab desk at the west side of the room
    http://www.globalindustrial.com/p/work-benches/systems/adjustable-height/72-l-x-36-w-production-bench-esd-square-edge-blue-2
  • Ordered clean / ESD  stools (~25" height)
    http://www.globalindustrial.com/p/office/stools/vinyl/esd-safe-vinyl-clean-room-stool-with-nylon-base-with-drag-chain-blue
  • Asked Gina for the electronics rack
    www.racksolutions.com/server-racks-cabinets-enclosures.html
    36U Height / 20" depth + Caster kit
  • 5 shelves ordered from AlliedElectronics (Quest technology ES0319-0115, 19"x15" non-vented shelf)
    http://www.racksolutions.com/rack-shelves
  • Plug slits on the roof of the HEPA booth (Peter)
  • Laser safety barrier (Peter) [ELOG]
  • Workbenches and clean room stools [ELOG]
  • OMC Mirros have been delivered (~Oct 10)
  • Halogen light source has been delivered
  • UV light guide has been delivered
     
• Things ordered
  
  • Office Depot
    • [delivered] Office Depot(R) Brand Stretch Wrap Film, 20 x 1000 Roll, Clear / 445013
    • [delivered] Eveready(R) Gold AA Alkaline Batteries, Pack Of 24 / 158448
    • [delivered] Rubbermaid(R) Roller Sponge Mop / 921841
    • [delivered] Rubbermaid(R) Roller Sponge Mop Replacement / 921858
    • [delivered] Rubbermaid(R) Sanitizing Caddy, 10 Quarts, Yellow / 674125
    • [delivered] Glad(R) Tall Kitchen Trash Bags, 13 Gallon, White, Box Of 28 / 269268
  • Global Industrial Equipment
    
    • [delivered] Extended Surface Pleated Cartridge Filter Serva-Cell Mp4 Slmp295 12X24X2 Gl    WBB431699
  • Global Industrial Equipment
    
    • [delivered] Nexel Poly-Z-Brite Wire Shelving 30"W x 21"D x 63"H Nexel Poly-Z-Brite™ Wire Shelving Starter Unit WB189209
    • [delivered] Stem Casters Set of (4) 5" Polyurethane Wheel, 2 With Brakes 1200 lb. Capacity WB500592    
  • Rack Solutions
    • [delivered] Open Frame Server Racks
      1 x 20" Depth Kit (Ideal for Audio/Video or Networking Racks) P/N: 111-1779
      1 x 36U, Rack-111 Post Kit P/N: 111-1728
      1 x Caster Kit for Open Frame RACK-111 P/N: 111-1731
    • [delivered] 36U Side Panel Kit $199.99 P/N: 102-1775
  • Rack shelf
    • [delivered] 1 RMS 19 X 15 SINGLE SIDED NON-VENTED SHELF 70121637
  • Work bench, Stools
    • [not yet] 72"L X 30"W Production Bench - Phenolic Resin Square Edge-Blue Form attached WB237381LBL    
    • [not yet] 72"W Lower Shelf For Bench - 15"D- Blue Form attached WB606951    
    • [not yet] ESD-Safe Vinyl Clean Room Stool with Nylon Base with Drag Chain Blue Form attached WBB560852    
  • P Touch
    • [delivered] Brother PT-2030 Desktop Office Labeler Punch-out product 672828    
    • [delivered] Brother(R) TZe-241 Black-On-White Tape, 0.75 x 26.2 Punch-out product 239384    
    • [delivered] Brother(R) TZe-231 Black-On-White Tape, 0.5 x 26.2 Punch-out product 239400    
      
  • UV light guide
    • [delivered] Fiber Optic Single Light Guide 5mm OD X 3mm ID X 1M L Note: This light guide can be used with MKIII UV Cure unit. OLB1081
  • Gloves (7.5, 8.0)
    • [delivered] GLOVE ACCTCH NR-LTX SZ7.5 PK25 Punch-out product 79999-306
    • [delivered] GLOVE ACCTCH NR-LTX SZ8 PK25 Punch-out product 79999-308
  • Lab coat (L,XL), Sticky Mat, Shoe Covers (L, XL), Cap, Mask
    • [delivered] LAB XP WH EL WR.COLL. NP L30EA Punch-out product 82007-618
    • [delivered] LAB XPWH EL WR.COLL. NP XL30EA Punch-out product 82007-620    
    • [delivered] VWR MAT ADHESIVE 30L 18X36 BLU Punch-out product 21924-110 (This was too small)
    • [delivered] VWR SHOECVR NSKID AP 2XL 150PR Punch-out product 414004-651    
    • [delivered] VWR SHOECVR NSKID AP XL 150PR Punch-out product 414004-650    
    • [delivered] CAP BOUFFANT 24IN RAYON CS500 Punch-out product 10843-053    
    • [delivered] MASK VLTC TIES N/STRL PK50 Punch-out product 10869-020
      
  • VWR
    • [delivered] FACE SHIELD UVC-803 Supplier: UVP 33007-151
       
  • [Delivered] Laser safety glasses
    
    • 35-200 Laser Glasses (PN 100-35-200) Qty.2 Price 189.00 ea
      http://www.lasersafetyindustries.com/35_200_Laser_Safety_Glasses_p/35-200.htm
    • Black Sport-wrap Laser Glasses 950-3600 nm (PN 100-38-200) Qty.1 Price 169.00 ea
      http://www.lasersafetyindustries.com/Black_Sport_wrap_Glasses_Diode_Nd_YAG_Er_YAG_p/100-38-200.htm

Completed work of the previous months: [Jul] [Aug] [Sep] [Oct] [Nov] [Dec]

Facility/Supplies

• Work done
  • Particle Level measured / HEPA activated [ELOG]
  • Particle counter peripherals arrived ~Oct 12.
  • Making the OMC optical test setup [ELOG] [ELOG] [ELOG] [ELOG] [ELOG]
  • OMC Bread board dimensions / weights measurement by Jeff and Jam [ELOG]
  • UV epoxy has arrived - stored in a freezer in the office
    • UV cured epoxy (Quote obtained)
      
    • Electronic Materials Inc.'s Optocast 3553LV-UTF-HM
      (A Low Viscosity, Ultra Thin Film epoxy with Heat Mechanism. The assembly/cure procedure includes both a UV binding step and a 120 degree cure for 24 hours.)
    • Ref1: Dennis Coyne, LIGO-E960050-v11,
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=3879
    • Ref2: Tobin Fricke, LIGO Document P1000010-v1, Homodyne detection for laser-interferometric gravitational wave detectors
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=8443
    • Ref3: OMC Construction Wiki https://awiki.ligo-wa.caltech.edu/aLIGO/OMC_Construction
    • The glue should be stored at T<0degC ==> Freezer in a lab
  • Laser sign installed during my trip by Peter/Eric
  • OMC design downselect [DCC Link]
     
• Things to buy
  
  • OMC testing optics / opto-mechanics
  • Power strips Tripp Lite PS3612
  • Lab coats
• Things to be done
  
  • Cavity ref/trans/finesse
  • PD Q.E. & Reflectivity measurement vs incident angle

• Work in progress
  
  • RoC measurement
  • R&T measurement
  • Wedge measurement
• Work to be done
  • Replacing a file cabinet next to the south wall by a lockable cabinet
  • Additional clean supplies ~ glove 8.5,9,9.5
  • Stainless bats
  • Ion gun safety issues: https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=88631
     　
• Design
  • Laser SOP
     
• Test
  • Continuous monitoring of the particle level
     
• Note: Optical Table W96" x D48" x H27"

Beaurocracy

• Laser SOP / HV use? / UV?

• Procedures to be decided
  • PZT alignment
  • UV glue? (heat) / gluing test
  • Balance
  • N2 cylinder/lines/filter

• Design
  
  • Mode design for HAM6 layout
  • Finalization of scattering paths
     
• Things to be decided / confirmed
  • How to handle optics / assemblies (Talk to the prev people)
  • First contact? (Margot: applicable to a short Rc of ~2.5m)
  • Gluing templates to be designed (how to handle it?)
     
• PDs
  • Primary choice for DC PD: Exelitas C30665GH 3mm
    Peter has plenty of them
    0.76A/W => Q.E. 0.88
    http://www.excelitas.com/downloads/dts_pe_pd_14_ingaasandsipindiodes.pdf
     
  • Primary choice for DC QPD: OSI FCI-InGaAs-Q3000
• Things to buy
  
  • Black Glass / Black Glass holder
  • Acetone.
  • N2 cylinder: 4N - UHP or 5N - Research Grade.
  • Paper lens tissue
  • Lint free cloth
  • The ionized gun used in the clean room at Downs: made by Terra Universal.com
    http://www.terrauniversal.com/static-control/ionizing-blow-off-guns.php
  • Flow path: N2 cylinder - Filter - Gun
  • Freezer
  • Clean tools, tray, storage

• Need to buy a fiber for mode cleaning?
  
• Mode content of the ELIGO dark beam?
• Jitter noise?
• How to determine the design?
• Why Fused Silica? (How much is the temp fluctuation in the chamber?)
• How to align the cavity mirrors, input mirrors, QPDs, PDs, beam dumps.
• PZTs @LLO
   

Electronics

• Thorough scrutinization of cabling / wiring / electronics
  • ELIGO OMC Wiring diagram D070536-A2
    • Occupies 2 DB25s -> They were anchored on the sus cage
    • Preamps for DCPDs will be fixed on the ISI table
      -> DB25 for the DCPDs will be anchored on the table
    • Use longer thin cables for the DCPDs in order to route them through the suspension stages
    • Turn the heater cable to the one for the other PZT
• Electronics / CDS electronics / software
• Things to be tested
  • QPD/PD pre-selections (QE/noise)
  • PD preamp design (Rich)
  • Functionality test of QPD/PD/PZT

Shipping, storage etc

• Shipping cage drawing
  https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=70209

The RoC test setup has been built on the optical table at ATF.

The cavity formed by actual OMC mirrors have been locked.

The modulation frequency of the BB EOM was swept by the network analyzer.
A peak at ~30MHz was found in the transfer function when the input beam was misaligned and clipping was introduced at the transmission PD.
Without either the misalignment or the clipping, the peak disappears. Also the peak requires these imperfections to be directed in the same way
(like pitch and picth, or yaw and yaw). This strongly suggests that the peak is associated with the transverse mode.

The peak location was f_HOM = 29.79MHz. If we consider the length of the cavity is L=1.20m, the RoC is estimated as

RoC = L / (1 - Cos[f_HOM/(c/2/L) * PI]^2)

This formula gives us the RoC of 2.587 m.

I should have been able to find another peak at f_FSR-f_TMS. In deed, there was the structure found at 95MHz as expected.
However, the peak was really weak and the location was difficult to determine as it was coupled with the signal from residual RFAM.

The particle level in the clean booth was occasionally measured. Every measurement showed "zero".

To be improved:

• The trans PD is 1801 which was found in ATF with the label of the 40m. It turned out that it is a Si PD.
  I need to find an InGaAs PD (1811, 1611, or my BBPD) or increase the modulation, or increase the detected light level.
  (==> The incident power on 1810 increased. Oct 17)
• The BS at the transmission is actually Y1-45P with low incident angle. This can be replaced by 50% or 30% BS to increase the light on the fast PD.
  (==> 50% BS is placed. Oct 17)
• I forgot to put a 50ohm terminator for the BB EOM.
  (==> 50Ohm installed. Oct 17)
• A directional coupler could be used for the BBEOM signal to enhance the modulaiton by 3dB.
• The mode matching is shitty. I can see quite strong TEM20 mode.
• Use the longer cavity? L=1.8m is feasible on the table. This will move the peak at 27MHz and 56MHz (FSR=83MHz). Very promising.
  (==> L=1.8m, peak at 27MHz and 56MHz found. Oct.17)

Significant improvement has been achieved in the RoC measurement.

• The trans PD has much more power as the BS at the cavity trans was replaced by a 50% BS. This covers the disadvantage of using the a Si PD.
• The BB EOM has a 50Ohm terminator to ensure the 50Ohm termination at Low freq.
• The length of the cavity was changed from 1.2m to 1.8m in order to see the effect on the RoC measurement.

By these changes, dramatic increase of the signal to noise ratio was seen.

Now both of the peaks corresponds to the 1st-order higher-order modes are clearly seen.
The peak at around 26MHz are produced by the beat between the carrier TEM00 and the upper-sideband TEM01 (or 10).
The other peak at around 57MHz are produced by the lower-sideband TEM01 (or 10).

Peak fitting

From the peak fitting we can extract the following numbers:

• Cavity FSR (hence the cavity length)
• Cavity g-factor
• Approximate measure of the cavity bandwidth

Note that the cavity itself has not been touched during the measurement.
Only the laser frequency and the incident beam alignment were adjusted.

The results are calculated by the combination of MATLAB and Mathemaica. The fit results are listed in the PDF files.
In deed the fitting quality was not satisfactory if the single Lorentzian peak was assumed.
There for two peaks closely lining up with different height. This explained slight asymmetry of the side tails
This suggests that there is slight astigmatism on the mirrors (why not.)

The key points of the results:

- FSR and the cavity length: 83.28~83.31MHz / L=1.799~1.800 [m] (surprisingly good orecision of my optics placement!)

- Cavity g-factor: Considering the flatness of the flat mirror from the phase map, the measured g-factors were converted to the curvature of the curved mirror.
RoC = 2.583~4 [m] and 2.564~7 [m]. (Note: This fluctuation can not be explained by the statistical error.)
The mode split is an order of 10kHz. This number also agrees with the measurement taken yesterday.

If the curved mirror had the nominal curvature of 2.5m, the flat mirror should have the curvature of ~20m. This is very unlikely.

- Approximate cavity line width: FWHM = 70~80kHz. This corresponds to the finesse of ~500. The design value is ~780.
This means that the locking offset is not enough to explain the RoC discrepancy between the design and the measurement.

Wedge angle test

Result: Wedge angle of Prism A1: 0.497 deg +/- 0.004 deg

Principle:

o Attach a rail on the optical table. This is the reference of the beam.

o A CCD camera (Wincam D) is used for reading out spot positions along the rail.

o Align a beam path along the rail using the CCD.

o Measure the residual slope of the beam path. (Measurement A)

o Insert an optic under the test. Direct the first surface retroreflectively. (This means the first surface should be the HR side.)

o Measure the slope of the transmitted beam. (Measurement B)

o Deflection angle is derived from the difference between these two measurements.

Setup:

o An Al plate of 10" width was clamped on the table. Four other clamps are located along the rail to make the CCD positions reproducible.

o A prism (Coating A, SN: A1) is mounted on a prism mount. The first surface is aligned so that the reflected beam matches with the incident beam
with precision of +/-1mm at 1660mm away from the prism surface. ==> precision of +/- 0.6mrad

o In fact, the deflection angle of the transmission is not very sensitive to the alignment of the prism.
The effect of the misalignment on the measurement is negligible.

o Refractive index of Corning 7980 at 1064nm is 1.4496

Result:

Without Prism
Z (inch / mm), X (horiz [um] +/-4.7um), Y (vert [um] +/-4.7um)
0” / 0, -481.3, -165.1
1.375" / 34.925, -474.3, -162.8
3" / 76.2, -451.0, -186.0
4.375" / 111.125, -432.5, -181.4
6" / 152.4, -432.5, -181.4
7.375" / 187.325, -330.2, -204.6
9" / 228.6, -376.7, -209.3

With Prism / SN of the optic: A1
Z (inch / mm), X (horiz [um] +/-4.7um), Y (vert [um] +/-4.7um)
0” / 0, -658.3, -156.8
1.375" / 34.925, -744.0, -158.1
3" / 76.2, -930.0, -187.4
4.375" / 111.125, -962.6, -181.4
6" / 152.4, -1190.4, -218.6
7.375" / 187.325, -1250.9, -232.5
9" / 228.6, -1418.3, -232.5

Analysis:

Wedge angle of Prism A1: 0.497 deg +/- 0.004 deg

[Click for a sharper image]

Completed work of the previous months: [Jul] [Aug] [Sep] [Oct] [Nov] [Dec]

• Work done
  • Particle Level measured / HEPA activated [ELOG]
  • Particle counter peripherals arrived ~Oct 12.
  • Making the OMC optical test setup [ELOG] [ELOG] [ELOG] [ELOG] [ELOG]
  • OMC Bread board dimensions / weights measurement by Jeff and Jam [ELOG]
  • UV epoxy has arrived - stored in a freezer in the office
    • UV cured epoxy (Quote obtained)
      
    • Electronic Materials Inc.'s Optocast 3553LV-UTF-HM
      (A Low Viscosity, Ultra Thin Film epoxy with Heat Mechanism. The assembly/cure procedure includes both a UV binding step and a 120 degree cure for 24 hours.)
    • Ref1: Dennis Coyne, LIGO-E960050-v11,
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=3879
    • Ref2: Tobin Fricke, LIGO Document P1000010-v1, Homodyne detection for laser-interferometric gravitational wave detectors
      https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=8443
    • Ref3: OMC Construction Wiki https://awiki.ligo-wa.caltech.edu/aLIGO/OMC_Construction
    • The glue should be stored at T<0degC ==> Freezer in a lab
  • Laser sign installed during my trip by Peter/Eric
  • OMC design downselect [DCC Link]

Completed work of the previous months: [Jul] [Aug] [Sep] [Oct] [Nov] [Dec]

• Work done
  • Wedge measurement (1st trial) [ELOG]
  • RoC measurement [ELOG]

• Work in progress
  
  • R&T measurement
  • Wedge measurement
• Work to be done
  • QPD/PD pre-selections (QE/noise)
  •  
  •  
  •  
  • Misc. / Beaurocracy?
    • Continuous monitoring of the particle level
    • Replacing a file cabinet next to the south wall by a lockable cabinet
    • Ion gun safety issues: https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=88631
    • Laser SOP / HV use? / UV?
• Things delivered
  • The ionized gun used in the clean room at Downs: made by Terra Universal.com (Jeff's room)
    http://www.terrauniversal.com/static-control/ionizing-blow-off-guns.php
  • Flow path: N2 cylinder - Filter - Gun (Jeff's room)
• Things ordered
  • Power strips Tripp Lite PS3612 (Ordered Nov. 8, Delivered Nov. 12)
  • Kapton tapes (1in x 6, 1/2in x 12 Delivered Nov. 15)
  • Sticky Mats (VWR 18888-216 Delivered Nov. 12 and 21992-042)
  • Duck tape (PK3) (Delivered Nov. 12)
  • Wipers 12"x12" 2ply x 119 pairs x case15 (Delivered Nov. 12)
  • Syringes (1mL&2mL) & Needles (20G x dozen)
  • Stainless trays with cover (Steve Delivered Nov. 12)
  • Gold Plated allen keys (Steve Delivered Nov. 12)
  • Forceps (Delivered Nov. 12) / Tweezers / Scissors (Delivered Nov. 12)
• Things to buy / get
  
  • OMC testing optics / opto-mechanics
  • Black Glass / Black Glass holder / AR ==> Some at the 40m, some from LLO
  • Ionized air blow
    • N2 or Air cylinder: 4N - UHP or 5N - Research Grade.  (... steal from Downs)
  • Clean tools, tray, storage
  • Supply
    
    • Additional clean supplies ~ glove 8.5,9,9.5
    • Stainless bats / Pure solvents (Metha / Aceton / Iso) / Syringes / Lint free cloth / Paper lens tissue
    • Lab coats
  • ATF
    • Tefron tape
    • Thorlabs 8-32 screw kit / Thorlabs HW-KIT1
    • Pedestal Shims - Newport
• Things to be done
  
  • Cavity ref/trans/finesse
  • PD Q.E. & Reflectivity measurement vs incident angle
  • Functionality test of QPD/PD (PeterK) /PZT
     

• Procedures to be decided
  • PZT alignment
  • UV glue? (heat) / gluing test
  • Balance
  • N2 cylinder/lines/filter
  • Shipping procedure: New shipping cage design on going (Jeff) => Plastic box similar to COC

• Design
  
  • Solidworks raytracing model
  • Mode design for HAM6 layout
     
• Things to be decided / confirmed
  • How to handle optics / assemblies (Talk to the prev people)
  • First contact? (Margot: applicable to a short Rc of ~2.5m)
  • Gluing templates to be designed (how to handle it?)

• Jitter noise?
• How to align the cavity mirrors, input mirrors, QPDs, PDs, beam dumps.

Electronics ==> Rich

A1
Horiz Wedge    0.497    +/-    0.004 deg
Vert Wedge      0.024    +/-    0.004 deg

A2
Horiz Wedge    0.549    +/-    0.004 deg
Vert Wedge      0.051    +/-    0.004 deg

A3
Horiz Wedge    0.463    +/-    0.004 deg
Vert Wedge      0.009    +/-    0.004 deg

A4
Horiz Wedge    0.471    +/-    0.004 deg
Vert Wedge      0.019    +/-    0.004 deg

A5
Horiz Wedge    0.458    +/-    0.004 deg
Vert Wedge      0.006    +/-    0.004 deg

Rich saids:

I have ordered a small roll of solder for the OMC piezos. 
The alloy is: Sn96.5 Ag3.0 Cu0.5

KA's question:

Do you know how to apply this epoxy?
Do we need a plunger and a needle for this purpose?

Nic saids:

When we did it with Sam, I seem to remember just squirting some on some foil then dabbing it on with the needle.

Optical prisms 50pcs (A14+B12+C6+E18)
Curved Mirrors 25pcs (C13+D12)

Now it's enough for the first OMC (or even second one too).
Today's measurements all distributed in theta>0.5deg. Is this some systematic effect???
I should check some of the compeled mirrors again to see the reproducibility...

A1    Horiz Wedge    0.497039    +/-    0.00420005    deg / Vert Wedge     0.02405210    +/-    0.00420061    deg

A2    Horiz Wedge    0.548849    +/-    0.00419993    deg / Vert Wedge     0.05087730    +/-    0.00420061    deg
A3    Horiz Wedge    0.463261    +/-    0.00420013    deg / Vert Wedge     0.00874441    +/-    0.00420061    deg
A4    Horiz Wedge    0.471536    +/-    0.00420011    deg / Vert Wedge     0.01900840    +/-    0.00420061    deg
A5    Horiz Wedge    0.458305    +/-    0.00420014    deg / Vert Wedge     0.00628961    +/-    0.00420062    deg

B1    Horiz Wedge    0.568260    +/-    0.00419988    deg / Vert Wedge    -0.00442885    +/-    0.00420062    deg
B2    Horiz Wedge    0.556195    +/-    0.00419991    deg / Vert Wedge    -0.00136749    +/-    0.00420062    deg
B3    Horiz Wedge    0.571045    +/-    0.00419987    deg / Vert Wedge     0.00897185    +/-    0.00420061    deg
B4    Horiz Wedge    0.563724    +/-    0.00419989    deg / Vert Wedge    -0.01139000    +/-    0.00420061    deg
B5    Horiz Wedge    0.574745    +/-    0.00419986    deg / Vert Wedge     0.01718030    +/-    0.00420061    deg
E1    Horiz Wedge    0.600147    +/-    0.00419980    deg / Vert Wedge     0.00317778    +/-    0.00420062    deg
E2    Horiz Wedge    0.582597    +/-    0.00419984    deg / Vert Wedge    -0.00537131    +/-    0.00420062    deg
E3    Horiz Wedge    0.592933    +/-    0.00419982    deg / Vert Wedge    -0.01082830    +/-    0.00420061    deg

-------

To check the systematic effect, A1 and B1 were tested with different alignment setup.

A1    Horiz Wedge    0.547056    +/-    0.00419994    deg / Vert Wedge    0.0517442    +/-    0.00420061    deg
A1    Horiz Wedge    0.546993    +/-    0.00419994    deg / Vert Wedge    0.0469938    +/-    0.00420061    deg
A1    Horiz Wedge    0.509079    +/-    0.00420003    deg / Vert Wedge    0.0240255    +/-    0.00420061    deg

B1    Horiz Wedge    0.547139    +/-    0.00419994    deg / Vert Wedge    0.0191204    +/-    0.00420061    deg



 

Mirror T test

The mirror was misaligned to have ~2deg incident (mistakenly...) angle.

C1: Ptrans = 7.58uW, Pinc = 135.0mW => 56.1ppm

C1 (take2): Ptrans = 7.30uW, Pinc = 134.4mW => 54.3ppm

C2: Ptrans = 6.91uW, Pinc = 137.3mW => 50.3ppm

C3: Ptrans = 6.27uW, Pinc = 139.7mW => 44.9ppm

C4: Ptrans = 7.62uW, Pinc = 139.3mW => 54.7ppm

C5: Ptrans = 6.20uW, Pinc = 137.5mW => 45.1ppm

A1: Ptrans = 1.094mW, Pinc = 133.6mW => 8189ppm

In order to resume testing the curvatures of the mirrors, the same mirror as the previous one was tested.
The result looks consistent with the previous measurement.

It seems that there has been some locking offset. Actually, the split peaks in the TF@83MHz indicates
the existence of the offset. Next time, it should be adjusted at the beginning.

Curved mirror SN: C1
RoC: 2.5785 +/- 0.000042 [m]

Previous measurements
=> 2.5830, 2.5638 => sqrt(RoC1*RoC2) = 2.5734 m
=> 2.5844, 2.5666 => sqrt(RoC1*RoC2) = 2.5755 m

C1: RoC: 2.57845 +/− 4.2e−05m

C2: RoC: 2.54363 +/− 4.9e−05m

C3: RoC: 2.57130 +/− 6.3e−05m   

C4: RoC: 2.58176 +/− 6.8e−05m

C5: RoC 2.57369 +/− 9.1e−05m

==> 2.576 +/- 0.005 [m] (C2 excluded)

The thicknesses of the prism mirrors (A1-A5) were measured with micrometer thickness gauge.
Since the thickness of the thinner side (side1) depends on the depth used for the measurement,
it is not accurate. Unit in mm.

A1: Side1: 9.916, Side2: 10.066 => derived wedge angle: 0.43deg
A2: Side1: 9.883, Side2: 10.065 => 0.52
A3: Side1: 9.932, Side2: 10.062 => 0.38
A4: Side1: 9.919, Side2: 10.060 => 0.40
A5: Side1: 9.917, Side2: 10.058 => 0.40

Steve and I visited Margot to have a training session for application of First Contact on optics.

- Make "thick" layer of first contact. It becomes thin when it gets dried.

- Apply more FC once a peek sheet is placed on the FC

- Wait for drying (~15min)

- Rip off the FC layer by pulling a peek tab. Make sure the ionized N2 is applied during ripping.

- Margot has a Dark Field Microscope. We checked how the dusts are removed from the surface.
There are many dusts on the mirror even if they are invisible. First Contact actually removes
these dusts very efficiently. Margot told us that even carbonhydrates (like finger prints) can be removed by FC.

Two switches are connected in series.

Completed work of the previous months: [Jul] [Aug] [Sep] [Oct] [Nov] [Dec]

• Work done
  • Wedge measurement (1st trial) [ELOG]
  • RoC measurement [ELOG]
  • Laser SOP draft

• Things delivered
  • The ionized gun used in the clean room at Downs: made by Terra Universal.com (Jeff's room)
    http://www.terrauniversal.com/static-control/ionizing-blow-off-guns.php
  • Flow path: N2 cylinder - Filter - Gun (Jeff's room)
  • Power strips Tripp Lite PS3612 (Ordered Nov. 8, Delivered Nov. 12)
  • Kapton tapes (1in x 6, 1/2in x 12 Delivered Nov. 15)
  • Sticky Mats (VWR 18888-216 Delivered Nov. 12 and 21992-042)
  • Duck tape (PK3) (Delivered Nov. 12)
  • Wipers 12"x12" 2ply x 119 pairs x case15 (Delivered Nov. 12)
  • Syringes (1mL&2mL) & Needles (20G x dozen)
  • Stainless trays with cover (Steve Delivered Nov. 12)
  • Gold Plated allen keys (Steve Delivered Nov. 12)
  • Forceps (Delivered Nov. 12) / Tweezers / Scissors (Delivered Nov. 12)
  • OMC testing optics / opto-mechanics
  • SolidWorks raytracing model
  • Mode design for HAM6 layout [Zach]
     
  • Black Glass / Black Glass holder / AR ==> Some at the 40m, some from LLO
  • Ionized air blow
    • N2 or Air cylinder: 4N - UHP or 5N - Research Grade.  (... steal from Downs)

Total (excluding C2, C7, C8): 2.575 +/- 0.005 [m]

New results

C6: RoC: 2.57321 +/− 4.2e-05m

C7: RoC: 2.56244 +/− 4.0e−05m ==> Polaris mount

C8: RoC: 2.56291 +/− 4.7e-05m ==> Ultima mount

C9: RoC: 2.57051 +/− 6.7e-05m

Previous results

C1: RoC: 2.57845 +/− 4.2e−05m

C2: RoC: 2.54363 +/− 4.9e−05m ==> Josh Smith @Fullerton for scattering measurement

C3: RoC: 2.57130 +/− 6.3e−05m   

C4: RoC: 2.58176 +/− 6.8e−05m

C5: RoC 2.57369 +/− 9.1e−05m

Measured the thickness of a curved mirror:

Took three points separated by 120 degree.

S/N: C2, (0.2478, 0.2477, 0.2477) in inch => (6.294, 6.292, 6.292) in mm